Glue and process of making same



Patented Jan. 31, 1933 UNITED STATES HENRY V. DUNHAM, OI BAINBRIDGE, NEW YORK GLUE AND PROCESS OF MAKING SAME 1T0 Drawing. Application filed April 16,

. This invention has for its object an improvement in certain types of cold water glues, and especially glues of the type used fcir gluing plywood, wood joints and the li (e;

It is known that such glues are generally made from milk-casein from vegetable proteinous substances such as peanut meal or soybean meal or the like, or from blends of these with milk-casein, together with solvents and mixtures of solvents well known in the art, namely lime, soda ash, trisodium phosphate, sodium fluoride, sodium sulfite, sodium silicate and the like.

These glues are generally dissolved or mixed with cold water and usually the amount of water used is from two to three parts to one of the dry glue;

It is known that suchglues under many formulas are of a rather heavy consistency and thus lack the smooth spreading properties and to some extent the penetrating qualities required to produce a strong joint. Of course, a glue that is too thick when dissolved can be thinned to any desired consistency by adding sufficient water, but when this is done, especially for Wood gluing, there are decided disadvantages. Thus; when too much water is used in diluting, the glue will not set quickly enough to permit removal from presses within the time usually allowed.

The glue'in this diluted condition may also have insuflicient holding qualities, and the excess moisture absorbed by the wood, may cause the wood to warp, check and assume irregular shapes.

These disadvantages are well known, and many attempts have been made to overcome them. Some of these attempts have been 40 based on the idea of adding to the liquid glue, or better, to the dry glue (base) amounts of inert or substantially inert mineral substances such as kieselguhr, whiting, gypsum and the like, to take the place of a portion of the protein and to thus produce a somewhat thin- I nor flowing glue, though of lower protein content. a

It was found that while such types of glue produce the desired results to some extent, the mineral substances so added have a very 1931. Serial No. 530,729.

bad dulling action on the knives, saws and cutting tools used in working the manufactured plywood, or other glued wood, thus necessitating frequent resharpening of the tools, or causing a relatively rough appearing cut.

For example a base having a composition (by weight) parts casein; 8 parts lime; 3 part trisodium phosphate; 4 parts sodium fluoride; 25 parts whiting; when dissolved 60 with two parts water to one part glue, will give a liquid glue of very good flow and consistency and satisfactory adhesive strength but it is very hard on the cutting tools, and for this reason, glues of this type, with high mineral content, have never been of commercial importance, so far as I am aware.

Other attempts have been made, by substituting insoluble organic substances, e. g. wood flour, in place of the inorganic materials mentioned. These substances, however, generally have an undesirable tendency .to increase the viscosity of the glue, due to the swelling or plumping caused by the action of the water and alkali.

I have discovered that this excessive thickening, which is characteristic of glues containing certain organic fillers, can be greatly reduced by the use of finely ground ivory nut, which moreover produces a comparatively soft glue-line, thus lessening the abrasive action on cutting tools.

The ivory-nut, also known as vegetable ivory or Corozo, is the fruit (seed) of certain trees such as Hyphaene thebaica, Phytelephas macrocarpa, Sagus Americanum and similar species. These nuts, after removal of the husk or outer shell, are largely used for the manufacture of buttons, beads, etc. and from this industry large amounts of waste accrue in the form of dust, parings and broken fragments. This waste material can be readily ground to a fine powder, in which form it may be incorporated in the glue-base. An analysis of ivory nut, given in the literature, shows that it consists mainly of nitro gen-free extract, (largely mannan with some pentosans), and a small percentage of protein.

The use of this material in the types of glue mo above referred to, constitutes the present invention.

To illustrate the relative effects of ivory nut flour and wood flour in a. casein glue base, the following comparisonmay be given. 100 parts of a casein glue base (G) having the percentage composition casein 76, lime 12, sodium carbonate 2, tri sodium phosphate 4, sodium fluoride 6, is dissolved in 200 parts of water, and the viscosity is determined by means of a Stormer viscosimeter. To compare with this, a mixture of 100 parts of the same casein glue base with, say 20 parts of ivory nut flour is prepared and the mixture then dissolved in twice its Weightof water i. e. 240 parts water. A similar mixture of 100 parts of the same casein glue base with 20 parts of wood flour is made up and dis solved in the same way. A series of such mixtures with increasing amounts of the respective filling agents, and dissolved in the fixed proportion of 1 part of the mixture to 2 parts of Water, are shown in the tabulation below. All mixtures are made under strict ly comparable conditions. The water is poured into a mixing kettle, and the glue is added slowly and stirred for 20 minutes. At

this time asample of the glue is transferred to the viscosimeter and the viscosity determined. The glue is then allowed to stand, and the viscosity is re-determined at intervals, say at 1 hour and 2 hours, reckoned from the moment of wetting the glue. It should be noted that the Stormer viscosimeter consists in principle of a cylinder rotating in a test cup filled with the liquid glue. The cylinder is driven by a constant weight (in the present case 500 grams) and the number of revolutions of the cylinder in a given time.,recorded on a dial, afford a comparison of the viscosity of the various liquids examined. A thick, viscous glue is indicated by a low reading on the dial, while a glue of thinner consistency shows a larger number of revolutions of the cylinder in unit time. The viscosity values given below represent the number of revolutions in 1 minute.

base G dissolved in two parts of water. Subsequent columns show the effect of addmg various amounts of ivory nut flour and Wood flour respectively. It will be seen that the effect of ivory nut flour (columns 2 to- 5) is to produce progressively thinner glues, while corresponding amounts of wood flour (columns 6 to 9) have the opposite effect.

Thus, where the initial viscosity of the original glue is 16, the addition of 20 parts of ivory nut flour to 100 parts of the glue base raises the initial viscosimeter reading to 28 (indicating a thinner glue), while the same amount of Wood flour decreases it to 6.

I have found that the proportion of ivory nut flour can be varied to a considerable extent depending upon the desired properties of the resulting glue, the glue formula used, and other factors. Various amounts between 5 parts and 100 parts added to 100 parts of the dry glue base can be employed.

In practicing this invention, the ivory nut or preferably the ivory nut waste from button manufacture, including as little of the shell of the nut as is practicable, is ground to a powder to pass substantially without residue through an 80 mesh sieve, or preferably finer, so that the major portion passes a 200 mesh sieve. This nut flour is then blended, in the desired proportion, with the ingredients to beused in making the dry glue (referred to herein as glue base). @r the ivory nut flour can be added in the dry form to any of the commercial cold water glues on the market.

The following are examples of satisfactory mixtures, these examples being given only by Way of illustration.

Example] Parts Casein 60 Lime 15 Tri sodium phosphate l Sodium fluoride 4: Ivory nut flour 17 The dry ingredients are thoroughly blended together. One part of this glue is then added to about two parts by weight of water in a kettle provided with an efficient stirrer. After mixing for about 20 minutes the glue is ready for use. Its consistency is similar to that of a thick cream.

Example I I Parts Casein 55.0 Lime 9.0 Sodium carbonate 3.0 Tri sodium phosphate L 1.5 Sodium fluoride 3.5

Ivory nut flour 28.0

This mixture is dissolved in about two parts of water as described under Example/I. The consistency of the fluid glue is somewhat Ivory nut flour 12 This dry mixture, after thoroughly blending, is preferably dissolved in 2 parts water. With this proportion of water the consistency is about the same as that of Example II and 5 is suitable for spreading b the mac ines employed'in the plywood in ustry.

It is of course to be understood that if desired, the ivory nut flour may be added to the water either before or after the glue base.

l0 For example, taking an average .grade of casein cold water glue, in powdered form, it is possible to utilize my process as follows Into a' mixin kettle provided with an agitator is place 200 lbs. of cold water preferably at 60 F. Twenty pounds of the ivory I nut flour is added, followed by 80 pounds of the commercial casein glue, and the mixing continued for about minutes, when the liquid glue is ready for use; the latter may then 20 be employed in the manner generally followed in the art, e. g. in making plywood.

Other ways of using this nut meal or flour, in regard to pro ortions used, and procedure will, of course, e apparent to one skilled in the art.

If desired I may first blend given amounts of the ground ivory nut with casein or vegetable proteinous material, and proceed to make the glue by adding this mixture to water, and then adding suitable chemicals such as lime and caustic soda; or lime and sodium silicate as described by Butterm'ann in U. S. Patent 1,291,396.

In any case, glues prepared according to this invention provide good flowing qualities, long liquid life, good adhesion and the general qualities desirable in a good cold water glue, at small expense.

I claim 40 1. In a glue of the type containing alkali and a proteinaceous su stance soluble in alkali solution, the herein described improvement which comprises the addition of ivory nut in a ulverulent state.

. 2. In t e art of making liquid glue from alkaline materials and a proteinaceous substance largely insoluble in water but soluble in alkali .solutions, the herein described step of adding powdered ivory nut.

3. A new base for the manufacture of adhesive compositions comprising a proteinaceous I substance largely insoluble in water but soluble in alkali solutions, powdered ivory nut and an alkali.

4. A new base for the manufacture of adhesive compositions comprising a proteinaceous substance largely insoluble in water but soluble in alkalis, powdered ivory nut, and an alkaline earth hydroxide together with an 80 alkali metal salt which in the presence of water can react with the said alkaline earth hydroxide to produce a solvent for the protein.

In testimony whereof I aflix my signature.

HENRY V. DUNHAM. 

